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41.
Potential for simultaneous improvement of grain and biomass yield in Central European winter triticale germplasm 总被引:1,自引:0,他引:1
Manje GowdaVolker Hahn Jochen C. ReifC. Friedrich H. Longin Katharina AlheitHans P. Maurer 《Field Crops Research》2011,121(1):153-157
Winter triticale, an abundant biomass source for producing biogas in Central Europe, has been bred until now for increased grain yield but not for early biomass yield. Therefore, our objectives were to assess the feasibility of breeding triticale for simultaneous improvement of early biomass and grain yield as well as to predict the early biomass yield using an index of traits measured at maturity stage. A representative sample of 100 triticale lines was evaluated in Experiment I at four locations in Germany. Traits were measured at two growth stages (early dough and full maturity). Genetic variances were significantly different from zero for all traits. The correlated response for early biomass yield estimated from grain yield (0.53) was high, which points to the efficiency of indirect selection. A multiple regression model was developed to predict early biomass yield. The reliability of the model was confirmed in an independent Experiment II with 49 lines. The calibration model explained 55% of total variation for early biomass yield. This clearly underlines that at least during earlier stages of selection, field testing can be carried out for grain yield and related traits to select potential genotypes with high biomass yield based on the developed regression model. 相似文献
42.
The present study’s aim was to test a German guideline for farm’s self-monitoring in sows and piglets for its feasibility as well as its interobserver and test–retest reliability. The study was performed between September 2016 and April 2018 on 13 farrowing farms in Northern Germany. Contrary to the guideline, the testing was not carried out by the farmers themselves but by 2 observers with experience in pigs representing common farmers. For the interobserver reliability study, the observers performed 20 joint farm visits independently assessing the same animals. For the test–retest reliability study, each farm was visited 5 times by 1 observer (day 0, day 3, week 7, month 5, month 10). Farm visit 1 (day 0) was used as reference and compared with the remaining farm visits. The reliability was evaluated using Spearman’s rank correlation coefficient (RS), intraclass correlation coefficient (ICC), and limits of agreement (LoA). As results, the guideline’s feasibility was limited. The indicators’ reliability also presented divergent results: All indicators in piglets revealed acceptable to good interobserver reliability (RS 0.64 to 0.77 ICC 0.33 to 0.48 LoA between the intervals −0.02 to 0.13 and −0.02 to 0.00). Contrarily, interobserver reliability was low for indicators in sows (e.g., claw alterations: RS −0.41 ICC 0.00 LoA −0.97 to 0.68). Overall acceptable test–retest reliability could be assigned to all indicators although no exact agreement existed but only the pursuit of trends is indicated. On the basis of the present results, the guideline in its present form cannot be recommended for farms’ self-monitoring. Given the restricted applicability, it should be reconsidered whether it might not be more appropriate to use scientifically tested and generally accepted animal welfare assessment systems such as the Welfare Quality animal welfare assessment protocols, although their application is also time-consuming. 相似文献
43.
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45.
Friedrich Moll 《Forstwissenschaftliches Centralblatt》1926,48(8):541-544
Ohne Zusammenfassung 相似文献
46.
Friedrich Moll 《Forstwissenschaftliches Centralblatt》1925,47(3):225-230
Ohne Zusammenfassung 相似文献
47.
48.
Dr. Friedrich Zacher 《Journal of pest science》1935,11(6):63-66
Ohne Zusammenfassung
Mit 1 Abbildung. 相似文献
49.
Maria-Elisabeth Krautwald-Junghanns DrMedVet Friedrich Schumacher AR DrMed Bernd Tellhelm AOR DrMedVet 《Veterinary radiology & ultrasound》1993,34(6):382-390
In the last 21 /2 years, 288 grey parrot and amazon species with symptoms of respiratory disease clinically were presented to the clinic for avian medicine at the Justus-Liebig-University in Giessen. Ventro-dorsal and latero-lateral radiographs were taken from all birds; radiologic signs of lower respiratory tract disease were noted. Radiographs were normal in 55 of the birds. The results of the radiographic examination for the remaining 233 birds were compared with the necropsy results of terminally ill parrots, with the results of laboratory examinations/endoscopy/and/or with an examination by computed tomography. Thoracic radiographs were evaluated for occurring radiological abnormalities pertaining to the respiratory tract. The frequency of these lesions and their association with a disease process and/or specific etiology was noted. 相似文献
50.
David O. Wallin Clive C. H. Elliott Herman H. Shugart Compton J. Tucker Friedrich Wilhelmi 《Landscape Ecology》1992,7(2):87-99
Data derived from the Advanced Very High Resolution Radiometer (AVHRR) on board the NOAA series of operational, polar orbiting,
meteorological satellites have previously been shown to be quite useful for monitoring vegetation dynamics at scales ranging
from regional (104 km2) to global. In this report, we demonstrate that these same data can be used to monitor potential breeding habitat for a highly
mobile, granivorous African weaver-bird, the red-billed quelea (Quelea quelea). This species is often considered to be an agricultural pest, affecting cereal production throughout sub-Saharan Africa.
The temporal resolution and very large (continental) spatial coverage provided by these data can provide a unique context
within which to examine species distribution and abundance patterns. 相似文献